William Whitelaw, 1st Viscount Whitelaw, Scottish-English politician, Deputy Prime Minister of the United Kingdom (d. 1999)
William Stephen Ian Whitelaw, 1st Viscount Whitelaw, (28 June 1918 – 1 July 1999) was a British Conservative politician who served in a wide number of Cabinet positions, most notably as Home Secretary from 1979 to 1983 and as de facto Deputy Prime Minister of the United Kingdom from 1979 to 1988. He was Deputy Leader of the Conservative Party from 1975 to 1991.After the Conservative Party won an unexpected victory at the 1970 general election, Whitelaw was appointed as Leader of the House of Commons and Lord President of the Council by Prime Minister Edward Heath. After the suspension of the Stormont Parliament resulted in the imposition of direct rule, Whitelaw served as Secretary of State for Northern Ireland from 1972 to 1973. He also served under Heath as Secretary of State for Employment from 1973 to 1974 and as Chairman of the Conservative Party from 1974 to 1975.

Whitelaw served Prime Minister Margaret Thatcher throughout her leadership of the Conservative Party as deputy party leader. He served as de facto Deputy Prime Minister between 1979 and 1988 and as Home Secretary from 1979 to 1983. He stepped down as a Member of Parliament at the 1983 general election, and was appointed as a Member of the House of Lords. He served as Leader of the House of Lords and Lord President of the Council from 1983 to 1988. He was a captain of The Royal and Ancient Golf Club of St Andrews.